Scientists Scan 300 Million Year Old Brain

Researchers using holotomography to create 3D images of fossilized
fish have found
a 300 million year old intact brain in a specimen from Kansas. This
is the oldest known example of any type of brain and should providing
some interesting new insights into brain evolution and function. The
visual lobe and optic nerve look similar to modern
brains but the area that regulates orientation and
balance doesn't connect to three ear canal loops. Instead, the
orientation sense is a flat plane, so the fish could sense side to side
movements but not up and down. Also unusual, the brain is much smaller
than the brain case. Could it be brain shrinkage after the
animal's death? Alan Pradel, one of the researchers, says
there is no sign of brain deformation that would result from
shrinkage and some very old existing fish species such as coelacanths
have a similar arrangement. Ironically, a
Walmart store now covers the location where the Kansas fossil
originated from but scientists plan to scan similar fossils found in
Oklahoma and Texas. For more details see the 3D video of the brain scan
after the break or the press release from
ESRF, where the brain was scanned, or the recent Neurophilosophy
or Neurobiotaxis blog
posts. For all the technical details,
see the paper on the find, Skull and
brain of a 300-million-year-old chimaeroid fish revealed by synchrotron
holotomography